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        <h1>太阳系行星数据</h1>
        太阳系中行星的一些数据。（资料取自<a href="https://nssdc.gsfc.nasa.gov/planetary/factsheet/">NASA 行星数据 -
            公制</a>，图片取自<a href="https://www.nasa.gov/multimedia/imagegallery/index.html">NASA 照片库</a>）

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                <th scope="col" id="name">名字</th>
                <th scope="col" id="weight">质量 (10<sup>24</sup>kg)</th>
                <th scope="col" id="d">直径 (km)</th>
                <th scope="col" id="dentisy">密度 (kg/m<sup>3</sup>)</th>
                <th scope="col" id="G"> 重力 (m/s<sup>2</sup>)</th>
                <th scope="col" id="time">天长 (hours)</th>
                <th scope="col" id="distance"> 与太阳距离 (10<sup>6</sup>km)</th>
                <th scope="col" id="averT">平均温度 (°C)</th>
                <th scope="col" id="number"> 卫星数量</th>
                <th scope="col" id="ps">备注</th>
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                <th colspan="2" rowspan="4" scope="rowgroup">类地行星</th>
                <th scope="row">水星</th>
                <td>0.330</td>
                <td>4,879</td>
                <td>5427</td>
                <td>3.7</td>
                <td>4222.6</td>
                <td>57.9</td>
                <td>167</td>
                <td>0</td>
                <td> 与太阳最近</td>
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                <th scope="row">金星</th>
                <td>4.87</td>
                <td>12,104</td>
                <td>5243</td>
                <td>8.9 </td>
                <td>2802.0</td>
                <td>108.2</td>
                <td>464</td>
                <td>0</td>
                <td></td>
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                <th scope="row">地球</th>
                <td>5.97</td>
                <td>12,756</td>
                <td>5514</td>
                <td>9.8</td>
                <td>24.0</td>
                <td>149.6</td>
                <td>51</td>
                <td>1</td>
                <td>我们的世界</td>
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                <th scope="row">火星</th>
                <td>0.642</td>
                <td>6,792 </td>
                <td> 3933 </td>
                <td>3.7 </td>
                <td>24.7</td>
                <td>227.9</td>
                <td>-65</td>
                <td>2</td>
                <td>红色星球</td>
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                <th rowspan="4" scope="rowgroup">类木行星</th>
                <th rowspan="2" scope="rowgroup">气巨星</th>
                <th scope="row">木星</th>
                <td>1898</td>
                <td>142,984</td>
                <td>1326</td>
                <td>23.1</td>
                <td>9.9 </td>
                <td>778.6 </td>
                <td> -110</td>
                <td> 67 </td>
                <td>太阳系最大</td>
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                <th scope="row">土星</th>
                <td>568</td>
                <td>120,536</td>
                <td>687</td>
                <td>9.0</td>
                <td>10.7</td>
                <td>1433.5</td>
                <td>-140</td>
                <td> 62</td>
                <td></td>
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                <th rowspan="2" scope="rowgroup">冰巨星</th>
                <th scope="row">天王星</th>
                <td>86.8</td>
                <td>51,118</td>
                <td>1271</td>
                <td>8.7</td>
                <td> 17.2</td>
                <td>2872.5</td>
                <td>-195 </td>
                <td> 27</td>
                <td></td>
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                <th scope="row">海王星</th>
                <td>102</td>
                <td>49,528</td>
                <td>1638 </td>
                <td> 11.0</td>
                <td>16.1</td>
                <td>4495.1</td>
                <td>-200</td>
                <td>14</td>
                <td></td>
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                <th scope="row" colspan="2">矮行星</th>
                <th scope="row">冥王星</th>
                <td>0.0146</td>
                <td>2,370 </td>
                <td> 2095 </td>
                <td> 0.7</td>
                <td>153.3 </td>
                <td>5906.4</td>
                <td> -225 </td>
                <td>5 </td>
                <td>2006年降格，但 <a
                        href="http://www.usatoday.com/story/tech/2014/10/02/pluto-planet-solar-system/16578959/">尚存争议</a>.
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